diff --git a/src/main/java/algorithm/conversions/HexadecimalToBinary.java b/src/main/java/algorithm/conversions/HexadecimalToBinary.java
new file mode 100644
index 0000000..340e0eb
--- /dev/null
+++ b/src/main/java/algorithm/conversions/HexadecimalToBinary.java
@@ -0,0 +1,45 @@
+package algorithm.conversions;
+
+/**
+ * program sederhana cara mengubah angka heksadesimal
+ * menjadi angka biner sebagai contoh
+ * 7F menjadi 1111111
+ */
+class HexadecimalToBinary {
+  private final int LONG_BIT = 8;
+
+  public String konversi(String angkaHex) {
+    int conHex = Integer.parseInt(angkaHex, 16);
+    String binary = Integer.toBinaryString(conHex);
+    return completeDigits(binary);
+  }
+
+  public String completeDigits(String angkaBiner) {
+    for (int i = angkaBiner.length(); i  < LONG_BIT; i++) {
+      angkaBiner = "0" + angkaBiner;
+    }
+    return angkaBiner;
+  }
+
+  public static void main(String[] args) {
+    String[] angkaHeksadesimal = {
+      "1",
+      "A1",
+      "ef",
+      "BA",
+      "AA",
+      "BB",
+      "19",
+      "01",
+      "02",
+      "03",
+      "04",
+    };
+    HexadecimalToBinary objectKonversi = new HexadecimalToBinary();
+    for (String angka : angkaHeksadesimal) {
+      System.out.println(angka + " = " + objectKonversi.konversi(angka));
+    }
+  }
+}
+
+